David Lammy, the Labour MP for Tottenham, has accused the prime minister and home secretary of abdicating responsibility after a fatal stabbing on Wednesday night brought the number of killings in London this year to more than 50.

Two 17-year-olds have been arrested on suspicion of the murder of an 18-year-old man in Hackney. Police said the victim was found by officers on Link Street just before 8pm on Wednesday with stab wounds. They did all they could to try to save him, rendering emergency first aid and chest compressions with the help of an off-duty paramedic until the ambulance service and London’s air ambulance arrived. But the victim died at the scene about 25 minutes later.

A police forensic tent remained on Morning Lane at the corner of Link Street on Thursday morning. A local youth worker said he had heard the victim was a former pupil of the nearby City Academy. “There’s a situation where kids are not scared of the justice system because it’s not harsh enough,” he said.

Lammy, who has been an MP for 18 years, told BBC Radio 4’s Today programme on Thursday: “What we’re seeing today is the worst I’ve ever seen it. There are parents, friends, families, schools traumatised and grieving. And there is absolutely no sign at the moment of reduction in the violence.

“There is no single cause. What I’m concerned about is what drives the gangs in the turf wars, and that’s an £11bn cocaine drugs market. We are the drugs market of Europe, and I think the police and our country have lost control of that drugs market. You have children as young as 12, 13, being recruited into gangs to run drugs.

“I’m hearing nothing about what we’re going to do. Drugs are prolific. It’s like Deliveroo, they’re as prolific as ordering a pizza. You can get them on Snapchat, WhatsApp. That in the end is driving the turf war and it’s driving the culture of violence that’s now becoming endemic.”

The Metropolitan police commissioner, Cressida Dick, on Thursday pledged to use “Al Capone” tactics to tackle the surge in violent crime. A new taskforce of 120 officers will focus on the most violent gang members and individuals to take them off the capital’s streets “for any crime”, she told the London Evening Standard.

Speaking at the scene on Thursday morning, the shadow home secretary and Hackney North MP, Diane Abbott, said: “It’s really tragic, it’s really horrible and mothers all over the capital must be thinking, ‘I can say goodbye to my son this morning but will he come back tonight?’ Whether their son will turn out to be a victim or a perpetrator, it’s traumatising for families.”

Lammy said there were several “Mr Bigs” that headed structured organisations in the country. “It’s not young people in Tottenham who know where to get guns,” he said. “I do know from the police that there are big gangs, eastern European, Albanian, that traffic people and guns. It’s not being handled solely by the Met. We’ve cut our Border Force. The National Crime Agency, the lead agency in this regard, reports an increase in this activity.”

A forensic tent covers the scene where a man, aged 20, collapsed after being fatally stabbed in Hackney. Photograph: Christopher Furlong/Getty Images

All this, he added, had to be considered in the context of inequality, with high levels of youth unemployment among black males, and local authorities that have cut youth services and outreach programmes.

“We aren’t debating this in parliament. I’ve not had a phone call from the home secretary, I haven’t had a phone call from the mayor, no one’s come to visit my constituency. This is happening across London at large. I’m sick of the political football, what I want is a political consensus.”

Both Lammy and Abbott cited the example of Glasgow, which has dramatically cut its murder rate by taking a coordinated public health approach to knife crime through education, youth work and social services.

On Twitter, Lammy wrote:

David Lammy (@DavidLammy)

Is a life in my constituency worth less than a life elsewhere in our country? I have had four young people lose their lives since Christmas and not a single phone call or visit from the PM or Home Secretary. Where is the political consensus on a serious strategy? Enough is enough

Just four hours before Wednesday night’s stabbing, a 53-year-old man died following reports of an assault at a bookmakers in Upper Clapton Road after an altercation with another male who left the scene.

Ch Supt Sue Williams, leading Hackney borough, said they were “working hard to prevent further violence and keep people safe – we have extra officers on the streets, both highly visible and in plain clothes carrying out a range of intelligence-led operations and patrols”.

Wednesday’s attacks added to the UK’s soaring rate of knife crime, with fatal stabbings in England and Wales at their highest levels since 2010-11. The escalating violence has been especially acute in London, with 13 people killed within two weeks last month.

The mayor of Hackney, Philip Glanville, said there were multiple reasons behind the rise in violence, including reduced police resources and the role of social media.

inc. continued investment in dedicated youth work both from statutory services & community/vol. sector; close partnership between police, council & other agencies (like Hackney's Integrated Gangs Unit) but can't ignore impact of reduced police resources & role of social media 2/2

On Tuesday, 16-year-old Amaan Shakoor and 17-year-old Tanesha Melbourne were fatally shot in London. They were apparently casualties of gang violence.

Martin Griffiths, lead surgeon for trauma at Barts health trust, said knife and gun injuries had become a core part of his work, with children as young as 13 coming in with wounds.

“Some kids are gang involved, but more often than not it’s young people with poor impulse controls,” he told the Today programme, adding that “lack of positive role models, lack of mentorship, lack of support of youth” were factors behind the rise in violent crime.